merge

48 files changed, 227 insertions, 129 deletions

diff --git a/Makefile b/Makefile
index 8e3d608..690bfc3 100644
--- a/Makefile
+++ b/Makefile
@@ -6,16 +6,16 @@ build:
 	${GO} build -o dgrep ./cmd/dgrep/main.go
 	${GO} build -o dmap ./cmd/dmap/main.go
 	${GO} build -o dtail ./cmd/dtail/main.go
+install:
+	${GO} install ./cmd/dserver/main.go
+	${GO} install ./cmd/dcat/main.go
+	${GO} install ./cmd/dgrep/main.go
+	${GO} install ./cmd/dmap/main.go
+	${GO} install ./cmd/dtail/main.go
 clean:
 	ls ./cmd/ | while read cmd; do \
 	  test -f $$cmd && rm $$cmd; \
 	done
-install: build
-	cp -pv dserver ${GOPATH}/bin/dserver
-	cp -pv dcat ${GOPATH}/bin/dcat
-	cp -pv dgrep ${GOPATH}/bin/dgrep
-	cp -pv dmap ${GOPATH}/bin/dmap
-	cp -pv dtail ${GOPATH}/bin/dtail
 vet:
 	find . -type d | egrep -v '(./samples|./log|./doc)' | while read dir; do \
 	  echo ${GO} vet $$dir; \
@@ -24,8 +24,8 @@ vet:
 lint:
 	${GO} get golang.org/x/lint/golint
 	find . -type d | while read dir; do \
-	  echo ${GOPATH}/bin/golint $$dir; \
-	  ${GOPATH}/bin/golint $$dir; \
+	  echo golint $$dir; \
+	  golint $$dir; \
 	done
 test:
 	${GO} test ./... -v
diff --git a/cmd/dcat/main.go b/cmd/dcat/main.go
index 05e46ab..c59a242 100644
--- a/cmd/dcat/main.go
+++ b/cmd/dcat/main.go
@@ -29,6 +29,7 @@ func main() {
 	flag.BoolVar(&debugEnable, "debug", false, "Activate debug messages")
 	flag.BoolVar(&displayVersion, "version", false, "Display version")
 	flag.BoolVar(&noColor, "noColor", false, "Disable ANSII terminal colors")
+	flag.BoolVar(&args.Quiet, "quiet", false, "Quiet output mode")
 	flag.IntVar(&args.ConnectionsPerCPU, "cpc", 10, "How many connections established per CPU core concurrently")
 	flag.IntVar(&sshPort, "port", 2222, "SSH server port")
 	flag.StringVar(&args.Discovery, "discovery", "", "Server discovery method")
diff --git a/cmd/dgrep/main.go b/cmd/dgrep/main.go
index 133631f..276dff4 100644
--- a/cmd/dgrep/main.go
+++ b/cmd/dgrep/main.go
@@ -31,6 +31,7 @@ func main() {
 	flag.BoolVar(&debugEnable, "debug", false, "Activate debug messages")
 	flag.BoolVar(&displayVersion, "version", false, "Display version")
 	flag.BoolVar(&noColor, "noColor", false, "Disable ANSII terminal colors")
+	flag.BoolVar(&args.Quiet, "quiet", false, "Quiet output mode")
 	flag.IntVar(&args.ConnectionsPerCPU, "cpc", 10, "How many connections established per CPU core concurrently")
 	flag.IntVar(&sshPort, "port", 2222, "SSH server port")
 	flag.StringVar(&args.Discovery, "discovery", "", "Server discovery method")
diff --git a/cmd/dmap/main.go b/cmd/dmap/main.go
index 9f9ca9d..a954e45 100644
--- a/cmd/dmap/main.go
+++ b/cmd/dmap/main.go
@@ -34,6 +34,7 @@ func main() {
 	flag.BoolVar(&debugEnable, "debug", false, "Activate debug messages")
 	flag.BoolVar(&displayVersion, "version", false, "Display version")
 	flag.BoolVar(&noColor, "noColor", false, "Disable ANSII terminal colors")
+	flag.BoolVar(&args.Quiet, "quiet", false, "Quiet output mode")
 	flag.IntVar(&args.ConnectionsPerCPU, "cpc", 10, "How many connections established per CPU core concurrently")
 	flag.IntVar(&args.Timeout, "timeout", 0, "Max time dtail server will collect data until disconnection")
 	flag.IntVar(&sshPort, "port", 2222, "SSH server port")
diff --git a/cmd/dtail/main.go b/cmd/dtail/main.go
index aefaa6a..5d4bad1 100644
--- a/cmd/dtail/main.go
+++ b/cmd/dtail/main.go
@@ -42,6 +42,7 @@ func main() {
 	flag.BoolVar(&debugEnable, "debug", false, "Activate debug messages")
 	flag.BoolVar(&displayVersion, "version", false, "Display version")
 	flag.BoolVar(&noColor, "noColor", false, "Disable ANSII terminal colors")
+	flag.BoolVar(&args.Quiet, "quiet", false, "Quiet output mode")
 	flag.IntVar(&args.ConnectionsPerCPU, "cpc", 10, "How many connections established per CPU core concurrently")
 	flag.IntVar(&args.Timeout, "timeout", 0, "Max time dtail server will collect data until disconnection")
 	flag.IntVar(&pprof, "pprof", -1, "Start PProf server this port")
diff --git a/go.mod b/go.mod
index e95da7d..c19efe7 100644
--- a/go.mod
+++ b/go.mod
@@ -4,7 +4,8 @@ go 1.15
 
 require (
 	github.com/DataDog/zstd v1.4.5
-	golang.org/x/crypto v0.0.0-20200728195943-123391ffb6de
-	golang.org/x/lint v0.0.0-20200302205851-738671d3881b // indirect
-	golang.org/x/sys v0.0.0-20200812155832-6a926be9bd1d // indirect
+	golang.org/x/crypto v0.0.0-20201203163018-be400aefbc4c
+	golang.org/x/lint v0.0.0-20201208152925-83fdc39ff7b5 // indirect
+	golang.org/x/sys v0.0.0-20201207223542-d4d67f95c62d // indirect
+	golang.org/x/term v0.0.0-20201207232118-ee85cb95a76b // indirect
 )
diff --git a/go.sum b/go.sum
index 00c6f54..c423bb0 100644
--- a/go.sum
+++ b/go.sum
@@ -8,10 +8,14 @@ golang.org/x/crypto v0.0.0-20191227163750-53104e6ec876 h1:sKJQZMuxjOAR/Uo2LBfU90
 golang.org/x/crypto v0.0.0-20191227163750-53104e6ec876/go.mod h1:LzIPMQfyMNhhGPhUkYOs5KpL4U8rLKemX1yGLhDgUto=
 golang.org/x/crypto v0.0.0-20200728195943-123391ffb6de h1:ikNHVSjEfnvz6sxdSPCaPt572qowuyMDMJLLm3Db3ig=
 golang.org/x/crypto v0.0.0-20200728195943-123391ffb6de/go.mod h1:LzIPMQfyMNhhGPhUkYOs5KpL4U8rLKemX1yGLhDgUto=
+golang.org/x/crypto v0.0.0-20201203163018-be400aefbc4c h1:9HhBz5L/UjnK9XLtiZhYAdue5BVKep3PMmS2LuPDt8k=
+golang.org/x/crypto v0.0.0-20201203163018-be400aefbc4c/go.mod h1:jdWPYTVW3xRLrWPugEBEK3UY2ZEsg3UU495nc5E+M+I=
 golang.org/x/lint v0.0.0-20200130185559-910be7a94367 h1:0IiAsCRByjO2QjX7ZPkw5oU9x+n1YqRL802rjC0c3Aw=
 golang.org/x/lint v0.0.0-20200130185559-910be7a94367/go.mod h1:3xt1FjdF8hUf6vQPIChWIBhFzV8gjjsPE/fR3IyQdNY=
 golang.org/x/lint v0.0.0-20200302205851-738671d3881b h1:Wh+f8QHJXR411sJR8/vRBTZ7YapZaRvUcLFFJhusH0k=
 golang.org/x/lint v0.0.0-20200302205851-738671d3881b/go.mod h1:3xt1FjdF8hUf6vQPIChWIBhFzV8gjjsPE/fR3IyQdNY=
+golang.org/x/lint v0.0.0-20201208152925-83fdc39ff7b5 h1:2M3HP5CCK1Si9FQhwnzYhXdG6DXeebvUHFpre8QvbyI=
+golang.org/x/lint v0.0.0-20201208152925-83fdc39ff7b5/go.mod h1:3xt1FjdF8hUf6vQPIChWIBhFzV8gjjsPE/fR3IyQdNY=
 golang.org/x/mod v0.1.1-0.20191105210325-c90efee705ee/go.mod h1:QqPTAvyqsEbceGzBzNggFXnrqF1CaUcvgkdR5Ot7KZg=
 golang.org/x/net v0.0.0-20190404232315-eb5bcb51f2a3/go.mod h1:t9HGtf8HONx5eT2rtn7q6eTqICYqUVnKs3thJo3Qplg=
 golang.org/x/net v0.0.0-20190620200207-3b0461eec859/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=
@@ -19,8 +23,16 @@ golang.org/x/sync v0.0.0-20190423024810-112230192c58/go.mod h1:RxMgew5VJxzue5/jJ
 golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
 golang.org/x/sys v0.0.0-20190412213103-97732733099d h1:+R4KGOnez64A81RvjARKc4UT5/tI9ujCIVX+P5KiHuI=
 golang.org/x/sys v0.0.0-20190412213103-97732733099d/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
+golang.org/x/sys v0.0.0-20191026070338-33540a1f6037/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20200812155832-6a926be9bd1d h1:QQrM/CCYEzTs91GZylDCQjGHudbPTxF/1fvXdVh5lMo=
 golang.org/x/sys v0.0.0-20200812155832-6a926be9bd1d/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
+golang.org/x/sys v0.0.0-20201119102817-f84b799fce68/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
+golang.org/x/sys v0.0.0-20201207223542-d4d67f95c62d h1:MiWWjyhUzZ+jvhZvloX6ZrUsdEghn8a64Upd8EMHglE=
+golang.org/x/sys v0.0.0-20201207223542-d4d67f95c62d/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
+golang.org/x/term v0.0.0-20201117132131-f5c789dd3221 h1:/ZHdbVpdR/jk3g30/d4yUL0JU9kksj8+F/bnQUVLGDM=
+golang.org/x/term v0.0.0-20201117132131-f5c789dd3221/go.mod h1:Nr5EML6q2oocZ2LXRh80K7BxOlk5/8JxuGnuhpl+muw=
+golang.org/x/term v0.0.0-20201207232118-ee85cb95a76b h1:a0ErnNnPKmhDyIXQvdZr+Lq8dc8xpMeqkF8y5PgQU4Q=
+golang.org/x/term v0.0.0-20201207232118-ee85cb95a76b/go.mod h1:bj7SfCRtBDWHUb9snDiAeCFNEtKQo2Wmx5Cou7ajbmo=
 golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
 golang.org/x/tools v0.0.0-20200130002326-2f3ba24bd6e7 h1:EBZoQjiKKPaLbPrbpssUfuHtwM6KV/vb4U85g/cigFY=
 golang.org/x/tools v0.0.0-20200130002326-2f3ba24bd6e7/go.mod h1:TB2adYChydJhpapKDTa4BR/hXlZSLoq2Wpct/0txZ28=
diff --git a/internal/clients/args.go b/internal/clients/args.go
index 34fcfa2..7f782f1 100644
--- a/internal/clients/args.go
+++ b/internal/clients/args.go
@@ -22,4 +22,5 @@ type Args struct {
 	SSHAuthMethods     []gossh.AuthMethod
 	SSHHostKeyCallback gossh.HostKeyCallback
 	PrivateKeyPathFile string
+	Quiet            bool
 }
diff --git a/internal/clients/baseclient.go b/internal/clients/baseclient.go
index d8d4fde..f20156f 100644
--- a/internal/clients/baseclient.go
+++ b/internal/clients/baseclient.go
@@ -39,7 +39,7 @@ type baseClient struct {
 }
 
 func (c *baseClient) init() {
-	logger.Info("Initiating base client")
+	logger.Debug("Initiating base client")
 
 	flag := regex.Default
 	if c.Args.RegexInvert {
@@ -66,11 +66,11 @@ func (c *baseClient) makeConnections(maker maker) {
 	c.stats = newTailStats(len(c.connections))
 }
 
-func (c *baseClient) Start(ctx context.Context, statsCh <-chan struct{}) (status int) {
+func (c *baseClient) Start(ctx context.Context, statsCh <-chan string) (status int) {
 	// Periodically check for unknown hosts, and ask the user whether to trust them or not.
 	go c.hostKeyCallback.PromptAddHosts(ctx)
 	// Print client stats every time something on statsCh is recieved.
-	go c.stats.Start(ctx, c.throttleCh, statsCh)
+	go c.stats.Start(ctx, c.throttleCh, statsCh, c.Args.Quiet)
 	// Keep count of active connections
 	active := make(chan struct{}, len(c.connections))
 
@@ -127,7 +127,7 @@ func (c *baseClient) makeConnection(server string, sshAuthMethods []gossh.AuthMe
 }
 
 func (c *baseClient) waitUntilDone(ctx context.Context, active chan struct{}) {
-	defer logger.Info("Terminated connection")
+	defer logger.Debug("Terminated connection")
 
 	// We want to have at least one active connection
 	<-active
diff --git a/internal/clients/catclient.go b/internal/clients/catclient.go
index d8e9196..b7b6131 100644
--- a/internal/clients/catclient.go
+++ b/internal/clients/catclient.go
@@ -42,8 +42,9 @@ func (c CatClient) makeHandler(server string) handlers.Handler {
 }
 
 func (c CatClient) makeCommands() (commands []string) {
+	options := fmt.Sprintf("quiet=%v", c.Args.Quiet)
 	for _, file := range strings.Split(c.What, ",") {
-		commands = append(commands, fmt.Sprintf("%s %s %s", c.Mode.String(), file, c.Regex.Serialize()))
+		commands = append(commands, fmt.Sprintf("%s:%s %s %s", c.Mode.String(), options, file, c.Regex.Serialize()))
 	}
 	return
 }
diff --git a/internal/clients/client.go b/internal/clients/client.go
index eb8452d..4a547e8 100644
--- a/internal/clients/client.go
+++ b/internal/clients/client.go
@@ -4,5 +4,5 @@ import "context"
 
 // Client is the interface for the end user command line client.
 type Client interface {
-	Start(ctx context.Context, statsCh <-chan struct{}) int
+	Start(ctx context.Context, statsCh <-chan string) int
 }
diff --git a/internal/clients/grepclient.go b/internal/clients/grepclient.go
index 4024083..652c31b 100644
--- a/internal/clients/grepclient.go
+++ b/internal/clients/grepclient.go
@@ -41,8 +41,10 @@ func (c GrepClient) makeHandler(server string) handlers.Handler {
 }
 
 func (c GrepClient) makeCommands() (commands []string) {
+	options := fmt.Sprintf("quiet=%v", c.Args.Quiet)
 	for _, file := range strings.Split(c.What, ",") {
-		commands = append(commands, fmt.Sprintf("%s %s %s", c.Mode.String(), file, c.Regex.Serialize()))
+		commands = append(commands, fmt.Sprintf("%s:%s %s %s", c.Mode.String(), options, file, c.Regex.Serialize()))
 	}
+
 	return
 }
diff --git a/internal/clients/handlers/basehandler.go b/internal/clients/handlers/basehandler.go
index b5045e2..f07fd90 100644
--- a/internal/clients/handlers/basehandler.go
+++ b/internal/clients/handlers/basehandler.go
@@ -4,7 +4,6 @@ import (
 	"encoding/base64"
 	"fmt"
 	"io"
-	"strconv"
 	"strings"
 	"time"
 
@@ -78,6 +77,7 @@ func (h *baseHandler) Read(p []byte) (n int, err error) {
 	case <-h.Done():
 		return 0, io.EOF
 	}
+
 	return
 }
 
@@ -111,21 +111,5 @@ func (h *baseHandler) handleHiddenMessage(message string) {
 		case <-h.Done():
 			return
 		}
-
-	case strings.HasPrefix(message, ".run exitstatus"):
-		splitted := strings.Split(strings.TrimSuffix(message, "\n"), " ")
-		if len(splitted) != 3 {
-			logger.Error("Unable to retrieve exitstatus", message)
-			return
-		}
-		i, err := strconv.Atoi(splitted[2])
-		if err != nil {
-			logger.Error("Unable to retrieve exitstatus", message, err)
-			return
-		}
-		logger.Debug("Retrieved exitstatus", h.status)
-		if i > h.status {
-			h.status = i
-		}
 	}
 }
diff --git a/internal/clients/handlers/healthhandler.go b/internal/clients/handlers/healthhandler.go
index 95693ab..0440706 100644
--- a/internal/clients/handlers/healthhandler.go
+++ b/internal/clients/handlers/healthhandler.go
@@ -19,6 +19,7 @@ type HealthHandler struct {
 	receive chan<- string
 	// The remote server address
 	server string
+	// The return status.
 	status int
 }
 
@@ -45,10 +46,12 @@ func (h *HealthHandler) Status() int {
 	return h.status
 }
 
+// Done returns done channel of the handler.
 func (h *HealthHandler) Done() <-chan struct{} {
 	return h.done.Done()
 }
 
+// Shutdown the handler.
 func (h *HealthHandler) Shutdown() {
 	h.done.Shutdown()
 }
diff --git a/internal/clients/maker.go b/internal/clients/maker.go
index 1ba6482..d5ffd8b 100644
--- a/internal/clients/maker.go
+++ b/internal/clients/maker.go
@@ -4,6 +4,9 @@ import (
 	"github.com/mimecast/dtail/internal/clients/handlers"
 )
 
+// maker interface helps to re-use code in all DTail client implementations.
+// All clients share the baseClient but have different connection handlers
+// and send different commands to the DTail server.
 type maker interface {
 	makeHandler(server string) handlers.Handler
 	makeCommands() (commands []string)
diff --git a/internal/clients/maprclient.go b/internal/clients/maprclient.go
index 149129d..1c0c2cc 100644
--- a/internal/clients/maprclient.go
+++ b/internal/clients/maprclient.go
@@ -94,12 +94,12 @@ func NewMaprClient(args Args, queryStr string, maprClientMode MaprClientMode) (*
 }
 
 // Start starts the mapreduce client.
-func (c *MaprClient) Start(ctx context.Context, statsCh <-chan struct{}) (status int) {
+func (c *MaprClient) Start(ctx context.Context, statsCh <-chan string) (status int) {
 	go c.periodicReportResults(ctx)
 
 	status = c.baseClient.Start(ctx, statsCh)
 	if c.cumulative {
-		logger.Info("Received final mapreduce result")
+		logger.Debug("Received final mapreduce result")
 		c.reportResults()
 	}
 
@@ -112,6 +112,7 @@ func (c MaprClient) makeHandler(server string) handlers.Handler {
 
 func (c MaprClient) makeCommands() (commands []string) {
 	commands = append(commands, fmt.Sprintf("map %s", c.query.RawQuery))
+	options := fmt.Sprintf("quiet=%v", c.Args.Quiet)
 
 	modeStr := "cat"
 	if c.Mode == omode.TailClient {
@@ -123,7 +124,7 @@ func (c MaprClient) makeCommands() (commands []string) {
 			commands = append(commands, fmt.Sprintf("timeout %d %s %s %s", c.Timeout, modeStr, file, c.Regex.Serialize()))
 			continue
 		}
-		commands = append(commands, fmt.Sprintf("%s %s %s", modeStr, file, c.Regex.Serialize()))
+		commands = append(commands, fmt.Sprintf("%s:%s %s %s", modeStr, options, file, c.Regex.Serialize()))
 	}
 
 	return
@@ -133,7 +134,7 @@ func (c *MaprClient) periodicReportResults(ctx context.Context) {
 	for {
 		select {
 		case <-time.After(c.query.Interval):
-			logger.Info("Gathering interim mapreduce result")
+			logger.Debug("Gathering interim mapreduce result")
 			c.reportResults()
 		case <-ctx.Done():
 			return
@@ -165,7 +166,7 @@ func (c *MaprClient) printResults() {
 	}
 
 	if numLines == 0 {
-		logger.Info("Empty result set this time...")
+		logger.Warn("Empty result set this time...")
 		return
 	}
 
diff --git a/internal/clients/stats.go b/internal/clients/stats.go
index e7eabd8..d8163d4 100644
--- a/internal/clients/stats.go
+++ b/internal/clients/stats.go
@@ -8,6 +8,7 @@ import (
 	"sync"
 	"time"
 
+	"github.com/mimecast/dtail/internal/config"
 	"github.com/mimecast/dtail/internal/io/logger"
 )
 
@@ -33,16 +34,18 @@ func newTailStats(connectionsTotal int) *stats {
 
 // Start starts printing client connection stats every time a signal is recieved or
 // connection count has changed.
-func (s *stats) Start(ctx context.Context, throttleCh, statsCh <-chan struct{}) {
+func (s *stats) Start(ctx context.Context, throttleCh <-chan struct{}, statsCh <-chan string, quiet bool) {
 	var connectedLast int
 
 	for {
 		var force bool
+		var messages []string
 
 		select {
-		case <-statsCh:
+		case message := <-statsCh:
+			messages = append(messages, message)
 			force = true
-		case <-time.After(time.Second * 2):
+		case <-time.After(time.Second * 3):
 		case <-ctx.Done():
 			return
 		}
@@ -52,11 +55,18 @@ func (s *stats) Start(ctx context.Context, throttleCh, statsCh <-chan struct{})
 
 		newConnections := connected - connectedLast
 
-		if connected == connectedLast && !force {
+		if (connected == connectedLast || quiet) && !force {
 			continue
 		}
 
-		logger.Info(s.statsLine(connected, newConnections, throttle))
+		stats := s.statsLine(connected, newConnections, throttle)
+		switch force {
+		case true:
+			messages = append(messages, fmt.Sprintf("Connection stats: %s", stats))
+			s.printStatsDueInterrupt(messages)
+		default:
+			logger.Info(stats)
+		}
 
 		connectedLast = connected
 		s.mutex.Lock()
@@ -65,6 +75,15 @@ func (s *stats) Start(ctx context.Context, throttleCh, statsCh <-chan struct{})
 	}
 }
 
+func (s *stats) printStatsDueInterrupt(messages []string) {
+	logger.Pause()
+	for _, message := range messages {
+		fmt.Println(fmt.Sprintf(" %s", message))
+	}
+	time.Sleep(time.Second * time.Duration(config.InterruptTimeoutS))
+	logger.Resume()
+}
+
 func (s *stats) statsLine(connected, newConnections int, throttle int) string {
 	percConnected := percentOf(float64(s.connectionsTotal), float64(connected))
 
@@ -88,5 +107,6 @@ func percentOf(total float64, value float64) float64 {
 	if total == 0 || total == value {
 		return 100
 	}
+
 	return value / (total / 100.0)
 }
diff --git a/internal/clients/tailclient.go b/internal/clients/tailclient.go
index 53b5ba4..cefbaa7 100644
--- a/internal/clients/tailclient.go
+++ b/internal/clients/tailclient.go
@@ -29,6 +29,7 @@ func NewTailClient(args Args) (*TailClient, error) {
 
 	c.init()
 	c.makeConnections(c)
+
 	return &c, nil
 }
 
@@ -37,8 +38,9 @@ func (c TailClient) makeHandler(server string) handlers.Handler {
 }
 
 func (c TailClient) makeCommands() (commands []string) {
+	options := fmt.Sprintf("quiet=%v", c.Args.Quiet)
 	for _, file := range strings.Split(c.What, ",") {
-		commands = append(commands, fmt.Sprintf("%s %s %s", c.Mode.String(), file, c.Regex.Serialize()))
+		commands = append(commands, fmt.Sprintf("%s:%s %s %s", c.Mode.String(), options, file, c.Regex.Serialize()))
 	}
 	logger.Debug(commands)
 
diff --git a/internal/color/colorfy.go b/internal/color/colorfy.go
index 9ae46f5..a2beb7a 100644
--- a/internal/color/colorfy.go
+++ b/internal/color/colorfy.go
@@ -41,16 +41,14 @@ func paintClientStats(line string) string {
 
 // Colorfy a given line based on the line's content.
 func Colorfy(line string) string {
-	if strings.HasPrefix(line, "REMOTE") {
+	switch {
+	case strings.HasPrefix(line, "REMOTE"):
 		return paintRemote(line)
-	}
-	if strings.HasPrefix(line, "CLIENT") && strings.Contains(line, "|stats|") {
+	case strings.HasPrefix(line, "CLIENT") && strings.Contains(line, "|stats|"):
 		return paintClientStats(line)
-	}
-	if strings.Contains(line, "ERROR") {
+	case strings.Contains(line, "ERROR"):
 		return Paint(Magenta, line)
-	}
-	if strings.Contains(line, "WARN") {
+	case strings.Contains(line, "WARN"):
 		return Paint(Magenta, line)
 	}
 
diff --git a/internal/config/common.go b/internal/config/common.go
index 103b390..c3e203e 100644
--- a/internal/config/common.go
+++ b/internal/config/common.go
@@ -2,10 +2,14 @@ package config
 
 // CommonConfig stores configuration keys shared by DTail server and client.
 type CommonConfig struct {
-	SSHPort                    int
+	// The SSH port number
+	SSHPort int
+	// Enable experimental features (mainly for dev purposes)
 	ExperimentalFeaturesEnable bool `json:",omitempty"`
-	DebugEnable                bool `json:",omitempty"`
-	TraceEnable                bool `json:",omitempty"`
+	// Enable debug logging. Don't enable in production.
+	DebugEnable bool `json:",omitempty"`
+	// Enable trace logging. Don't enable in production.
+	TraceEnable bool `json:",omitempty"`
 	// The log strategy to use, one of
 	//   stdout: only log to stdout (useful when used with systemd)
 	//   daily: create a log file for every day
diff --git a/internal/config/config.go b/internal/config/config.go
index dc96d6b..276ddcf 100644
--- a/internal/config/config.go
+++ b/internal/config/config.go
@@ -15,6 +15,9 @@ const ScheduleUser string = "DTAIL-SCHEDULE"
 // ContinuousUser is used for non-interactive continuous mapreduce queries.
 const ContinuousUser string = "DTAIL-CONTINUOUS"
 
+// InterruptTimeoutS is used to terminate DTail when Ctrl+C was pressed twice within a given interval.
+const InterruptTimeoutS int = 3
+
 // Client holds a DTail client configuration.
 var Client *ClientConfig
 
diff --git a/internal/config/server.go b/internal/config/server.go
index db12cec..dc0d587 100644
--- a/internal/config/server.go
+++ b/internal/config/server.go
@@ -61,6 +61,7 @@ type ServerConfig struct {
 	Continuous []Continuous `json:",omitempty"`
 }
 
+// ServerRelaxedAuthEnable should be used for development and testing purposes only.
 var ServerRelaxedAuthEnable bool
 
 // Create a new default server configuration.
diff --git a/internal/discovery/comma.go b/internal/discovery/comma.go
index 94276c7..4344240 100644
--- a/internal/discovery/comma.go
+++ b/internal/discovery/comma.go
@@ -1,8 +1,9 @@
 package discovery
 
 import (
-	"github.com/mimecast/dtail/internal/io/logger"
 	"strings"
+
+	"github.com/mimecast/dtail/internal/io/logger"
 )
 
 // ServerListFromCOMMA retrieves a list of servers from comma separated input list.
diff --git a/internal/discovery/file.go b/internal/discovery/file.go
index c04173e..1250755 100644
--- a/internal/discovery/file.go
+++ b/internal/discovery/file.go
@@ -2,8 +2,9 @@ package discovery
 
 import (
 	"bufio"
-	"github.com/mimecast/dtail/internal/io/logger"
 	"os"
+
+	"github.com/mimecast/dtail/internal/io/logger"
 )
 
 // ServerListFromFILE retrieves a list of servers from a file.
diff --git a/internal/io/fs/permissions/permission_linux.go b/internal/io/fs/permissions/permission_linux.go
index feae729..bbc039b 100644
--- a/internal/io/fs/permissions/permission_linux.go
+++ b/internal/io